Search form

Reassigning the Planets

We know that Pluto, formerly known as a planet, was downgraded in status to “dwarf planet” in 2006. But it is only now that I realized the implications of this reclassification.

Mercury, too, got reassigned. Mercury currently holds the designation (and might the small among us say pride) of the title of the smallest planet. Size-wise, it is only slightly larger than our moon.

Smallest is not Mercury’s only superlative. Its other claims to fame include closest, fastest and most elusive.

The sun’s nearest and dearest planet is Mercury. At only 36 million miles from the sun, it exists in close quarters to that significant star. If you could stand on Mercury, the sun would appear three times as big as it looks from Earth. This proximity makes it difficult for us to see the planet during the night and only allows us a brief glimpse at other times.

From Earth, Mercury can only be observed during the evening or early mornings. Occasionally we can see it during its transit across the sun, an event that will only happen 13 times during this century. The last transit was on Nov. 8, 2006 and the next one will happen on May 9, 2016.

However, this month is a good time to check out mysterious Mercury. During the middle of the month, the littlest planet can be seen best before sunrise in the eastern horizon low in the sky.

November is also good time to view other planets and sky stuff as well. Evenings will yield Venus in the southwest and Jupiter in the east. If you are an early bird, besides Mercury, search for Saturn toward the end of the month also in the east. On the night of Nov. 17 and morning of the 18th, the Leonid meteor showers will peak.

Even with this busy celestial month, Mercury still has a few fabulous features to fathom. While the planet rotates very slowly on its own axis, it makes up for it by its rapid revolutions around the sun. One day on Mercury is equal to 58.5 Earth days, but to circumnavigate the sun only 88 Earth days will pass! In fact, Mercury travels through space 112,000 miles per hour faster than any other planet.

This rapid orbit is likely how Mercury got its name. The Roman god Mercury was known for his winged shoes, which carried him at great speeds in his capacity as messenger to the gods. He was also the patron saint of financial gain, commerce, traders, trickery and thieves and carried souls to the underworld. This was all in a day’s work for the diligent deity. Conditions on Mercury are not welcoming for gods or humans: there is almost no atmosphere on Mercury. Without this protective shield to retain heat, surface temperatures vary greatly. Cold nights can drop to -280 degrees F, but things really heat up during the day, with temperatures that can rise to 800 degrees F.

Despite these harsh conditions, proximity to the sun, slow and fast rotations, isolation and barren surface, German poet and naturalist Johann Wolfgang von Goethe thought he could raise the status of Mercury. He declared that “I had rather be Mercury, the smallest among seven [planets], revolving round the sun, than the first among five [moons] revolving round Saturn.”

Little did he know, new discoveries would cause his petite planet to lose its designation only to later reclaim its tiny title.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.